This invention relates to an apparatus for longitudinally sealing and severing a packaging hose made of a thermoplastic film. The apparatus is intended for use particularly in packing machines.
Swiss Patent No. 527,090 discloses a sealing and severing apparatus for a packing machine. The thermoplastic film hose is obtained by folding it by a hose forming (hose folding) box about two columns of products and subsequently the two superposed films of the packing hose are sealed together lengthwise between the two product columns. Downstream of the cooperating advancing and sealing rollers the thus-formed two parallel hoses are severed from one another by means of a rotating circular knife which cooperates with a circular elastomer counter support.
German Offenlegungsschrift (application published without examination) No. 2,727,960 discloses another sealing and severing apparatus which has a heated circular severing knife. A plate, serving as a counter support, is provided with a longitudinal groove into which the knife projects. Additional advancing components are needed for conveying the film.